This is a single-center, exploratory, Phase 1 Positron Emission Tomography/x-ray Computed Tomography (PET/CT) imaging study to detect amyloidosis that will enroll patients with a confirmed diagnosis of systemic amyloidosis. The purpose of this exploratory trial is to assess the safety and efficacy of 124I-p5+14 Injection at a single-injection dose adequate for imaging amyloid deposits by using PET/CT imaging in subjects with confirmed systemic Immunoglobulin Light Chain-associated Amyloidosis (AL), Transthyretin-associated Amyloidosis (ATTR), Leukocyte Chemotactic Factor 2-associated Amyloidosis (ALect2) as well as other types.
The rationale for this study is the discovery of a synthetic polypeptide, designated p5+14, a synthetic 45 amino acid peptide that binds many forms of amyloid, including human AL-, ATTR- and ALect2-associated amyloid, as well as human and murine serum amyloid protein A-associated (AA) amyloid. In preclinical studies, using SPECT and PET imaging, as well as microautoradiography, it has been shown that radioiodinated p5+14 binds rapidly and specifically to all amyloid deposits in abdominothoracic organs and tissues. This is a single site, exploratory, open-label Phase I PET/CT imaging and dosimetry study. The investigational drug product (designated 124I-p5+14 Injection) is an amyloid-reactive synthetic peptide, p5+14 (also known as APi1832), radiolabeled with iodine-124 (I-124 or 124I). All patients enrolled in this exploratory trial will be outpatients with a confirmed diagnosis of systemic amyloidosis. The first three patients enrolled in the trial (Part 1) will take part in a dose-escalation dosimetry study and will receive a single intravenous (IV) dose of 11.1 Megabecquerel (MBq) (0.3 millicuries (mCi); n = 1), 37 MBq (1 mCi; n = 1) or 74 MBq (2 mCi; n = 1) of 124I-p5+14 Injection for the purpose of determining estimates of organ-associated and whole body radioactive dosimetry. The trial then will be opened to include another 54 patients who will receive a single IV bolus injection of 2 mCi 124I-p5+14 Injection. Every patient participating will receive \< 2 mg of peptide p5+14. The study comprises five parts. In Part 2, the trial will enroll SA patients with confirmed AL, ATTR, ALECT2, or other forms of amyloidosis. In Part 3, the trial will study asymptomatic subjects with genetically confirmed mutation of the transthyretin gene. Part 4 will include five healthy control subjects. Part 5 will recruit previously enrolled subjects from Parts 2 or 3 who received a 2 mC dose of 124I-p5+14 Injection and had images confirming the presence of abnormal amyloid deposits for a second exposure to 124I p5+14 Injection and second PET/CT scan.
Study Type
INTERVENTIONAL
Allocation
NA
Purpose
DIAGNOSTIC
Masking
NONE
Enrollment
57
124I-p5+14 Injection which is a formulation of a synthetic, all natural, 45 amino acid peptide (MW = 4766.4) with a net +12 positive charge
University of Tennessee Medical Center
Knoxville, Tennessee, United States
Organ-specific radioactivity dosimetry (Part 1).
Localization of 124I-p5+14 will be taken from PET/CT images performed at intervals during the 48 hours after injection. Organ-specific dosimetry and whole body dose measurements will be made using Olinda software (Olinda/Exp; Organ Level Internal Dose Assessment/Exponential Modeling)
Time frame: Through 48 hours
Absolute values and changes from baseline in clinical laboratory values.
Laboratory assessments will include hematology and clinical chemistry.
Time frame: Baseline and 24 hours
Clinically defined amyloidosis organ involvement.
For each subject, the clinician/investigator will designate each organ as involved or not involved with amyloidosis, based on available medical history including prior imaging, prior biopsy results, and clinical laboratory values.
Time frame: Baseline
Measure of background radioactivity uptake.
For each subject, a background radioactivity uptake measure will be derived from the PET images at an uninvolved anatomic site (the lumen of a large blood vessel).
Time frame: 6 hours and 24 hours
Measure of radioactivity uptake by each organ
Uptake of 124I-p5+14 will be derived from PET/CT scans performed at 6 hours and 24 hours after injection. Any organ with \>=2-fold higher accumulation of radiotracer, relative to the background uptake, will be considered positive.
Time frame: 6 hours and 24 hours
Concentration of radiotracer in specific anatomic sites, for each subject and anatomic site
Concentration of 124I-p5+14 will be derived from PET/CT scans performed at 6 hours and 24 hours after injection.
Time frame: 6 hours and 24 hours
Organ and tissue-specific sensitivity of the 124I-p5+14 Injection radiotracer
Sensitivity for each organ will be derived from the list of clinically involved organs (Secondary Measure 1) and the list of organ radioactivity uptake (Secondary Measure 4), using the formula, true positive rate = \[True positive/(True positive + False negative)\].
Time frame: 6 hours and 24 hours
Correlation between concentration of the radiotracer (Bq/cc) in the kidney with organ-associated clinical biomarkers.
Statistical correlation of kidney radiotracer uptake with proteinuria, albuminuria, creatinine, and blood urea nitrogen (BUN).
Time frame: 6 hours and 24 hours
Correlation between concentration of the radiotracer (Bq/cc) in the heart with organ-associated clinical biomarkers.
Statistical correlation of heart radiotracer uptake with N-terminal-pro-brain natriuretic peptide (NT-BNP) or Brain Natriuretic Peptide (BNP) serum levels, intraventricular septal thickness, and ejection fraction (measures as available from medical history)
Time frame: 6 hours and 24 hours
Peptide uptake in the heart.
Peptide uptake will be recorded as the Standard Uptake Value (SUV) or as Bq/cc of organ volume; obtained from the Region of Interest (ROI) analysis
Time frame: 6 hours and 24 hours
Peptide uptake in the kidney
Peptide uptake will be recorded as the Standard Uptake Value (SUV) or as Bq/cc of organ volume; obtained from the Region of Interest (ROI) analysis.
Time frame: 6 hours and 24 hours
Peptide uptake in organ(s) other than kidney or heart if clinically relevant
Peptide uptake will be recorded as the Standard Uptake Value (SUV) or as Bq/cc of organ volume; obtained from the Region of Interest (ROI) analysis
Time frame: 6 hours and 24 hours
Correlation between uptake of peptide and clinical status of kidney, heart and other organs
Correlation between uptake of peptide (from ROI measurements) and the clinical status of kidney, heart, and other organs if indicated (clinical status defined as in Secondary Endpoint 1).
Time frame: Baseline and 24 hours
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